It does seem odd that some brand new models in the lineup like the Cruze have this ability but others do not. It seems like anything with their 2.5L has had this disable removed. I find it hard to believe that their smaller engine is the one closer to the emission/fuel economy targets. Just a note that I don't think start/stop will be nearly as noticeable or jarring in the Blazer as models past. The tech has advanced a lot and its pretty seamless now.